Voice Over IP Lines

Your existing telephone system - upgraded.

What is SIP Trunking?

SIP Trunking refers to the use of VoIP to connect your premise based phone system to the Internet. A broadband or Internet connection replaces traditional, plain-old-telephone (POTs) or Primary Rate Interface (PRI) lines, allowing your organization to communicate more efficiently with better scalability.

SIP Trunking may be utilized with virtually any PBX system, including modern IP based phone systems or older styled analog systems. The older systems may require an integrated access device (IAD) to bridge the SIP connection to your PBX. Either way, SIP Trunking will bridge your company to the modern communications cloud, helping connect all office and mobile users together.


How SIP Trunking Works

SIP Trunking is an excellent way to take advantage of VoIP, while keeping your investment to a minimum, by utilizing your existing telephone system hardware. SIP Trunks will provide you with additional functionality and prepare to move to a fully Hosted PBX solution in the future.

As a successful business, you’re constantly searching for the next big thing. Whether you’re a small business looking for the flexibility and cost savings of VoIP, or a mid-sized company looking for business continuity and flexible calling plan options, we’ll help you save time and money over your traditional telephone services.

Session Initiation Protocol (SIP) is becoming the common signaling standard for your real-time communications that utilize VoIP (Voice over Internet Protocol). SIP enables you to seamlessly connect with your existing premise-based phone systems using our carrier class voice network.

We’ll provide you with as many SIP Trunk groups as you need, with an unlimited number of pre-paid call paths. Also, you’ll have the ability to burst up to ten additional call paths on demand for improved capacity planning.


The ability to burst above the number of pre-paid trunks or call paths on demand, automatically


Modify the platform as you need to, including scaling up/down, integration, with an intuitive interface, on our future-proofed platform

Advanced Call Routing

Provides you with advanced routing capabilities including call forwarding, and call status (away, busy, unreachable, etc.)

Multi-Office Trunking

Aggregate your SIP Trunks to leverage the savings from pooling and centralizing your communication needs at the enterprise level.

Business Continuity

We’ll provide you with improved disaster recovery options so you can sleep soundly in the event of a shutdown or natural disaster.

How to Switch

Interested in switching to CSII Voice? Call 770-834-2453 or click the button to the left to receive a customized quote detailing the benefits of utilizing our innovative products and services. When you’re ready, we’ll install your SIP trunks on your phone system with ZERO downtime, so you can get back to business.